1. Field of the Invention
The invention relates to an earplug commonly used by insertion within the human ear to reduce the amount of noise heard.
2. Description of Prior Art
Earplugs are well-known and are used both in industry and by individuals. The purpose of earplugs is to reduce noise exposure while providing a maximum of comfort to the user.
U.S. Pat. No. 3,301,243 to Glorig discloses an ear protector comprising a generally mushroom-shaped tip or head mounted on a stem. The stem itself is surrounded by a sleeve. A head set is used to bias two of the earplugs into the ears of the user.
U.S. Pat. No. 3,618,600 to Douglass allegedly represents an improvement over the Glorig earplug and attempts to provide greater comfort to the user. The stem portion of the plug is modified so as to increase its effective cross-sectional area thereby reducing the pressure on the ear in terms of force per unit area. The stem is modified by tapering it so as to provide a bulge as the plug is forced against the ear.
German Pat. No. 456,207 discloses an earplug having a mushroom-shaped tip as well as a stem having an orifice extending therethrough.
Swedish Pat. No. 399,178 discloses an earplug set connected by a cord. The front portion of the earplug is provided with an orifice in its outer surface.
U.S. Pat. No. 968,008 to Waller discloses a "noise arrestor" comprising plugs or buttons which are maintained within the ear for purposes of reducing sound transmission. FIG. 9 of the patent illustrates a plug having what would appear to be a hemispherical shape. A headband is used to maintain the plug within the ear.
U.S. Pat. No. 2,492,183 to Rosenblatt discloses an acoustic device made of a soft rubber having a mushroom-shaped head which is solid in cross-section.
U.S. Pat. Design No. 245,202 to Asker again discloses an earplug having a mushroom-shaped head.
Finally, U.S. Pat. No. 3,415,246 to Hill (FIGS. 7-10) illustrates an ear fitting having a generally mushroom-shaped tip or head. The fitting is used for purposes of transmitting sound rather than arresting sound transmission. The fitting is provided with an orifice through which the sound may pass.